Instead of open coding meta pointer accessing through caches. This patch introduces vhost_get_meta_ptr()/vhost_put_meta_ptr() pair to reduce the code duplication and simplify its callers implementation. This is helpful for reducing LOC for packed virtqueue as well.
Signed-off-by: Jason Wang <[email protected]> --- drivers/vhost/vhost.c | 207 ++++++++++++++---------------------------- 1 file changed, 70 insertions(+), 137 deletions(-) diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index dc9301d31f12..7f51c74d9aee 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -1194,25 +1194,37 @@ static inline void __user *__vhost_get_user(struct vhost_virtqueue *vq, ret; \ }) -static inline int vhost_put_avail_event(struct vhost_virtqueue *vq) -{ #if VHOST_ARCH_CAN_ACCEL_UACCESS +static void *vhost_get_meta_ptr(struct vhost_virtqueue *vq, int type) +{ struct vhost_map *map; - struct vring_used *used; if (!vq->iotlb) { rcu_read_lock(); + map = rcu_dereference(vq->maps[type]); + if (likely(map)) + return map->addr; + rcu_read_unlock(); + } + return NULL; +} - map = rcu_dereference(vq->maps[VHOST_ADDR_USED]); - if (likely(map)) { - used = map->addr; - *((__virtio16 *)&used->ring[vq->num]) = - cpu_to_vhost16(vq, vq->avail_idx); - rcu_read_unlock(); - return 0; - } +static void vhost_put_meta_ptr(void) +{ + rcu_read_unlock(); +} +#endif - rcu_read_unlock(); +static inline int vhost_put_avail_event(struct vhost_virtqueue *vq) +{ +#if VHOST_ARCH_CAN_ACCEL_UACCESS + struct vring_used *used = vhost_get_meta_ptr(vq, VHOST_ADDR_USED); + + if (likely(used)) { + *((__virtio16 *)&used->ring[vq->num]) = + cpu_to_vhost16(vq, vq->avail_idx); + vhost_put_meta_ptr(); + return 0; } #endif @@ -1225,23 +1237,14 @@ static inline int vhost_put_used(struct vhost_virtqueue *vq, int count) { #if VHOST_ARCH_CAN_ACCEL_UACCESS - struct vhost_map *map; - struct vring_used *used; + struct vring_used *used = vhost_get_meta_ptr(vq, VHOST_ADDR_USED); size_t size; - if (!vq->iotlb) { - rcu_read_lock(); - - map = rcu_dereference(vq->maps[VHOST_ADDR_USED]); - if (likely(map)) { - used = map->addr; - size = count * sizeof(*head); - memcpy(used->ring + idx, head, size); - rcu_read_unlock(); - return 0; - } - - rcu_read_unlock(); + if (likely(used)) { + size = count * sizeof(*head); + memcpy(used->ring + idx, head, size); + vhost_put_meta_ptr(); + return 0; } #endif @@ -1253,21 +1256,12 @@ static inline int vhost_put_used_flags(struct vhost_virtqueue *vq) { #if VHOST_ARCH_CAN_ACCEL_UACCESS - struct vhost_map *map; - struct vring_used *used; - - if (!vq->iotlb) { - rcu_read_lock(); + struct vring_used *used = vhost_get_meta_ptr(vq, VHOST_ADDR_USED); - map = rcu_dereference(vq->maps[VHOST_ADDR_USED]); - if (likely(map)) { - used = map->addr; - used->flags = cpu_to_vhost16(vq, vq->used_flags); - rcu_read_unlock(); - return 0; - } - - rcu_read_unlock(); + if (likely(used)) { + used->flags = cpu_to_vhost16(vq, vq->used_flags); + vhost_put_meta_ptr(); + return 0; } #endif @@ -1279,21 +1273,12 @@ static inline int vhost_put_used_idx(struct vhost_virtqueue *vq) { #if VHOST_ARCH_CAN_ACCEL_UACCESS - struct vhost_map *map; - struct vring_used *used; + struct vring_used *used = vhost_get_meta_ptr(vq, VHOST_ADDR_USED); - if (!vq->iotlb) { - rcu_read_lock(); - - map = rcu_dereference(vq->maps[VHOST_ADDR_USED]); - if (likely(map)) { - used = map->addr; - used->idx = cpu_to_vhost16(vq, vq->last_used_idx); - rcu_read_unlock(); - return 0; - } - - rcu_read_unlock(); + if (likely(used)) { + used->idx = cpu_to_vhost16(vq, vq->last_used_idx); + vhost_put_meta_ptr(); + return 0; } #endif @@ -1343,21 +1328,12 @@ static inline int vhost_get_avail_idx(struct vhost_virtqueue *vq, __virtio16 *idx) { #if VHOST_ARCH_CAN_ACCEL_UACCESS - struct vhost_map *map; - struct vring_avail *avail; - - if (!vq->iotlb) { - rcu_read_lock(); + struct vring_avail *avail = vhost_get_meta_ptr(vq, VHOST_ADDR_AVAIL); - map = rcu_dereference(vq->maps[VHOST_ADDR_AVAIL]); - if (likely(map)) { - avail = map->addr; - *idx = avail->idx; - rcu_read_unlock(); - return 0; - } - - rcu_read_unlock(); + if (likely(avail)) { + *idx = avail->idx; + vhost_put_meta_ptr(); + return 0; } #endif @@ -1368,21 +1344,12 @@ static inline int vhost_get_avail_head(struct vhost_virtqueue *vq, __virtio16 *head, int idx) { #if VHOST_ARCH_CAN_ACCEL_UACCESS - struct vhost_map *map; - struct vring_avail *avail; - - if (!vq->iotlb) { - rcu_read_lock(); - - map = rcu_dereference(vq->maps[VHOST_ADDR_AVAIL]); - if (likely(map)) { - avail = map->addr; - *head = avail->ring[idx & (vq->num - 1)]; - rcu_read_unlock(); - return 0; - } + struct vring_avail *avail = vhost_get_meta_ptr(vq, VHOST_ADDR_AVAIL); - rcu_read_unlock(); + if (likely(avail)) { + *head = avail->ring[idx & (vq->num - 1)]; + vhost_put_meta_ptr(); + return 0; } #endif @@ -1394,21 +1361,12 @@ static inline int vhost_get_avail_flags(struct vhost_virtqueue *vq, __virtio16 *flags) { #if VHOST_ARCH_CAN_ACCEL_UACCESS - struct vhost_map *map; - struct vring_avail *avail; - - if (!vq->iotlb) { - rcu_read_lock(); + struct vring_avail *avail = vhost_get_meta_ptr(vq, VHOST_ADDR_AVAIL); - map = rcu_dereference(vq->maps[VHOST_ADDR_AVAIL]); - if (likely(map)) { - avail = map->addr; - *flags = avail->flags; - rcu_read_unlock(); - return 0; - } - - rcu_read_unlock(); + if (likely(avail)) { + *flags = avail->flags; + vhost_put_meta_ptr(); + return 0; } #endif @@ -1419,19 +1377,12 @@ static inline int vhost_get_used_event(struct vhost_virtqueue *vq, __virtio16 *event) { #if VHOST_ARCH_CAN_ACCEL_UACCESS - struct vhost_map *map; - struct vring_avail *avail; + struct vring_avail *avail = vhost_get_meta_ptr(vq, VHOST_ADDR_AVAIL); - if (!vq->iotlb) { - rcu_read_lock(); - map = rcu_dereference(vq->maps[VHOST_ADDR_AVAIL]); - if (likely(map)) { - avail = map->addr; - *event = (__virtio16)avail->ring[vq->num]; - rcu_read_unlock(); - return 0; - } - rcu_read_unlock(); + if (likely(avail)) { + *event = (__virtio16)avail->ring[vq->num]; + vhost_put_meta_ptr(); + return 0; } #endif @@ -1442,21 +1393,12 @@ static inline int vhost_get_used_idx(struct vhost_virtqueue *vq, __virtio16 *idx) { #if VHOST_ARCH_CAN_ACCEL_UACCESS - struct vhost_map *map; - struct vring_used *used; - - if (!vq->iotlb) { - rcu_read_lock(); - - map = rcu_dereference(vq->maps[VHOST_ADDR_USED]); - if (likely(map)) { - used = map->addr; - *idx = used->idx; - rcu_read_unlock(); - return 0; - } + struct vring_used *used = vhost_get_meta_ptr(vq, VHOST_ADDR_USED); - rcu_read_unlock(); + if (likely(used)) { + *idx = used->idx; + vhost_put_meta_ptr(); + return 0; } #endif @@ -1467,21 +1409,12 @@ static inline int vhost_get_desc(struct vhost_virtqueue *vq, struct vring_desc *desc, int idx) { #if VHOST_ARCH_CAN_ACCEL_UACCESS - struct vhost_map *map; - struct vring_desc *d; - - if (!vq->iotlb) { - rcu_read_lock(); - - map = rcu_dereference(vq->maps[VHOST_ADDR_DESC]); - if (likely(map)) { - d = map->addr; - *desc = *(d + idx); - rcu_read_unlock(); - return 0; - } + struct vring_desc *d = vhost_get_meta_ptr(vq, VHOST_ADDR_DESC); - rcu_read_unlock(); + if (likely(d)) { + *desc = *(d + idx); + vhost_put_meta_ptr(); + return 0; } #endif -- 2.18.1
